The primary research objective of this study is to analyze barriers to ambulatory and long-term care services to determine their impact on resource utilization among the community-dwelling Medicare and Medicaid dual enrollee population age 65 and over. The 1999 Six State Survey of Dual Enrollees merged with 1998 and 1999 Medicare Claims Data will be used to analyze this topic. The Six State Survey is a cross-sectional survey of 2,128 community-dwelling individuals age 65 and over who have been continuously enrolled in the Medicare and Medicaid programs for at least 12 continuous months in Georgia, Iowa, New Jersey, Massachusetts, Washington, or Wisconsin. Despite the provision of health insurance to low-income seniors, access to health care problems persist. Low-income seniors are less likely to have access to a regular source of care, less likely to visit physicians compared to higher-income elderly individuals, and more likely to report unmet long-term care needs in the community. The results of these problems are increased rates of emergency department use, hospitalization, and mortality. The association of unmet ambulatory and long-term care needs of dually enrolled populations on health outcomes and Medicare expenditures has not been widely studied. The outcomes of interest include ambulatory care sensitive condition (ACSC) hospitalization and Medicare expenditures. ACSC hospitalizations are thought to be preventable with timely and effective ambulatory care. The impact of long-term care needs on ACSC hospitalization has never been studied. Key independent variables of interest include unmet need for long-term care measured by a need for (more) help from another person with activities of daily living (ADLs) or instrumental activities of daily living (IADLs), and organizational, financial, and geographic access to ambulatory care barriers. Exploratory data analyses will be used to analyze missing data, check the normality and linearity of the data, look for outliers, analyze variation between outcomes of interest and independent variables, and choose the correct functional forms for the multivariable models. Two-stage least squares models will be used to control for the endogeneity of the barriers variables. Multivariate logistic regression will be used to model the likelihood of an ACSC hospitalization for people reporting access to ambulatory or long-term care barriers controlling for need, enabling and predisposing factors, and community resources. Multivariate regression analyses will also be used to analyze the impact of the key independent variables on the log of Medicare expenditures controlling for other doctors. Access to care for the Medicaid population is an important issue to study in order to analyze the appropriateness and effectiveness of the Medicaid program in delivering services to vulnerable populations. If care under Medicaid is currently meeting the needs of dually enrolled elderly individuals, then any new funds should be directed to expanding eligibility. If care is inappropriate or ineffective, then expanded benefits or increased payments for current services may be more important.